Rotary motor



ROTARY MOTOR Filed Feb. 25, 1919 2 Sheets-Sheet 1 7-1 1 90 in R. 51.6,

mama Jan. 5, i926.

PATENT OFFICE.

moors nocnm om', or rams, rannca.

mm Moron.

' Application ma February 25, 1919. Serial No. 279,203.

To all whom it may concern {Beit known that I, FRANQOIS RooHEFonT, a citizen of the French Republic, and a resident of Paris, France, have invented certain new and useful Improvements in Rotary Motors, of which the following is a specification.

This invention relates to a polycylindrical rotary internal combustion motor, furnished with an annular body with rotating cylinders of circular form, in which the pistons which move are fixed to a single central piece in the form of Z, that moves in the direction of rotation of the cylinders at a variable angular speed.

According to this invention the movement of the central piece in the form of Z is effected through the medium of two-pairs of toggle links, connected on the one hand with the cylinders and on. the other hand with the said central piece, and having rollers bearing against two fixed twin cams. These latter are situated at opposite sides of the central planeof the annular body.

In the accompanying drawing .given by way of example Fig. 1 is a diagrammatic view of the motor, partly in section.-

Fig. 2 1s a similar view showing the movable parts in a different position.

Fig. 3 is a longitudinal sectionon'a larger scale showing the working of the valves.

' air.

Fig. .4 is a similar section showing the by the circulation of cooling arrangement This motor is com osed ofelements assembled in groups 0 two, each of which comprises two diametrically opposed cylinders C and C of circular section, each cylinder constituting 'a sector of about 70 of an annulus of circular cross section.

These cylinders are held in position at an uniform distance from the centre 0 of the motor by side cheeks F forming part of a casing, the cheeks being mounted on ball bearings the interior rings of which are fitted under considerable friction on a fixed hollow shaft A about which the motor ro- -tates.

The group consisting of the casing. and cylinders can rotate freely around the fixed shaft and bears at H the coupling device by which the power developed may be transmited to the machine or point where it is to be absorbed. On the fixed shaft A two twin cams K made of tempered steel having keyways corresponding to the shaft keys are non-rotatably mounted. These cams which are of special profile, are kept at a definite distance apart by the interposition of an annular oscillating hearing R the interior rim or crownof which acts as a distance piece.

On the large rim of the oscillating bearing R is mounted a central piece termi- .nating in two diametrically opposed curved.

arms running in the direction of the motor the whole constituting a rigid piece in theform of Z.

At the ends of the curved arms of the Z are rigidly fixed the pistons p and p which the shaft A whilst remaining at an uniform distance from the centre 0 (Figs. 1 and 2.)

The drivingconnection between the pis-' tons and the shaft A is formed by two diametrically opposite groups oftoggle links, each comprising,- a link B and a link B.

Each link- B is mounted to oscillate-- around a shaft X carried in hearings in a triangular bracket T formed in one piece with the cylinder and serving for center ing and "fixing it to the cheeks F. r The opposite end of each link B is arranged to engage a short shaft X.

The pair of parallel links B also engage the short shaft X and are held in position one-on each side of 'the link -B by antifriction rollers R whose inner bearing rings are locked in' place upon the ends of the shaft by nuts 0 as shown in Fig. 4.

The 0 posite ends of the parallel links B are fix under considerable friction on the shoulders of a short shaft X the central part of which oscillates in a bearing in the central piece Z.

The arrangement of the two opposed of the parallel links The shafts X -B and the shafts X through t e medium at first equal to that of the cylinders.

If an elastic resistance be interposed in one of the two cylinders say C between the end of the cyiinder' head and the piston the cylinder will have a tendency to move in the direction indicated and the piston in the reverse direction. The effect of this is to apply tension to the links B, B and in consequence cause the rollers R to press in a radial direction upon the cam K.

The rollers R are thus kept pressed against and caused to follow the path of the twin cams K.

Starting from the points N, N, the rollers R following the profile of the cams are moved away from the centre of the motor.

The group of cylinders and easing moving at a rotary speed which may be regarded as practically uniform the rollers R and consequently the shafts X move away from the centre of the motor; the result of which is that the shafts X and X come near to one another which causes an increase in the rotary speed of the pistons and consequently brings them nearer the ends or heads of the cylinders. \Vhen the rollers R are at M and M that is to say at the peaks of the cams, the pistons are at the end of their stroke in the direction of the cylinder heads Q, at inner dead centre.

The two pistons act simultaneously in their respective cylinders. I

Supposing that during this stroke towards the cylinder head, hereinafter referred to as the ascending stroke, the piston 12 has compressed an explosive mixture and after having passed the inner dead centre,

ignites this mixture so as to receive an im-' pulsive expansion.

The forces previously indicated having increased in value the general resultants tend to throw the shafts X towards the centre of the motor. But these shafts cannot move freely being guided by the rollers R which are always forced to 'roll on the cams the profile of which starting from the points M and M constitutes approximately a descending curve having the shaft X as centre.

Under the action of the resultant forces the rollers and consequently the shafts X describe a curve around the centre of the shafts X following the outline of the cams K which are fixed upon the stationary shaft A.

At this moment the shafts X are thus almost stationary and consequently the central piece 2; in consequence of which the pistons are also almost stationary and therefore serve as points of support to the expanding gases. The cylinders and casing block being free to move, increases its rtary speed and takes up the largest part of the energy furnished by the expansion of the gases.

Starting from a certain point the cam slope becomes tangential to the circumference passing through the point where the rollers R come nearest to the centre of the motor at N and N.

'The rollers engage on this S 0 and move away from the primitive position of the shafts X forcing these latter to move in the direction of rotation of the whole with increasing speed which becomes equal to that of the cylinders when the rollers pass at N and N and greater from those points up to M and M.

If we take again the movement at N and N Fig. 2, we see that a complete ascending stroke of the pistons is equal to 60 of movement of the pistons in the cylinders and 90 of movement of the cylinders around the centre 0, the pistons having moved 90 and 60:150 around the same centre.

The pistons having passed the inner dead centre, become stationary for a certain time and the descending stroke then takes placethrough the continuous movement of the cylinders. The pistons then 'move, but at a less speed than that of the cylinders up to the outer dead centre.

A second stroke of the pistons is effected after 90 of rotation of the cylinders the pistons also move in the same direction but only remaining in arrear 'lhus in this half rotation the cylinders have moved 90 or 180 and the pistons 150. and 30 or equally 180.

The second half rotation is effected in the same manner.

The cylinders move again twice 90:180 and the pistons 150 during one stroke and 30 during the other, which together make 180 around the centre 0.

Each piston having run four strokes in its cylinder during one complete revolution of the motor, the cycle is completed.

In looking at Figs. 1 and 2 it will be seen that when the cylinder C is in expansion stage the cylinder C is in the admission stage.

hen the cylinder C is in the exhaust stage, the cylinder C is in the compression stage.

hen the cylinder C is in the admission stage C is in the expansion stage.

When the cylinder C is in the compres sion stage C is in the exhaust stage.

In an element of two opposite cylinders the expansions follow one another at intervals of 180.

Thus double regularity for the same number of cylinders comparatively to an ordinary motor.

Distribution. (l' z'g. .The complete cycle being eifectedin one rotation of the the shields or tubes b motor the distribution devices must act in each cylinder once in each revolution.

For this purposeithe valve operating device moves at a rotary speed equal to that of the cylinders and once in each revolution passes in front of a fixed cam K which is held locked on the shaft A.

This kind of motor may have 1, 2, 3, or

.4 groups of two elements on a single shaft close eac valve at the starting of the motori.-

When the motor is running the closing is assured by the centrifugal force acting on the body of the valve.

The actuating rods t are moved towards the centre of the motor by the centrifugal force acting upon the valve bodies and upon counterweight situated opposite the rods on the levers Air supp y.The cylinders C and C are extended by sheet iron tubes V ut together in halves and forming a shiel This. ar-

rangement enables the oil to be caught when t is in excess and is projected towards the exterior from all the devices in movement in the interlor of the motor.

These tubes are open towards the interior of the motor so as to allow a free passage for the arms of the 2 piece carrying the pistons, and terminate in suction pipes which establish communication between the valve'boxes and the interior of the.tubes.

In order that the oil accumulated within centrifugal action may not enter the cylin ers the'suction pipes are each furnished internally with an oblique partition C.

The interior of the motor casing is in constant communication with the open air through openings 'Fig. 4 drilled laterally in the cheeks F towards the centre of the motor. I

The cylinders are furnished for the cooling. Each. of them has an attached head Q furnished with an admission valve S of large diameter. mounted on a tti-ng containinga suitable joint and secured by four nuts.

Exhaust openings or ports L formed at the outer end of the cylinder are uncov- .ered by the piston at the end of its exhaus tion stroke at the outer dead centre.

with vanes I p an's-The motor continuing its movement This head is These portsrun into an expansion chamber fitted and maintained by tightening on the outside of the cylinder. This chamber is placed in the'reverse direction to ,the rotation of the motor in order to increase the rapidity of flow of the gases passing into the interior. It has external y cast vanes w for the cooling.

' Supply of combustibles.-This motor is a high compression motor, the air alone is drawn by suction into the cylinders and powerfully compressed so as to raise the temperature sufliciently to allow of, the ignition of the combustible, vapours which are injected under pressure into the cylinders by independent piston pumps rotating with the motor; I

Practical cycle-working (Figs. 1 and :2) .Let us consider a single element formed by two diametrically o posite cylinders. The phenomena occur i entically in each of them but at an angle of 180 in relation to the rotation of the motor.

Admission of air-Let us cause the-motor to rotate in the direction of the arrow until its piston is at the end of thecourse atinner dead centre. The valve being open there is communication between the interior of the cylinder C and the casingthrough the Let us continue the rotation. The relative vacuum caused by the movement of the cylinder causes a volume of cold air to come in from the casing which latter is in constant communication with the open air through the openings 0, Fig. 4.

Thus at this movement there exists in the admission pipe a current of air the velocityof WlllClllIlCIGiLSGS rapidly in consequence of the linear velocity of the piston. This linear velocity diminishes in value until it suction pipe U.

reaches zero. At this moment the exhaust openings L are freed by the piston and from its movement. This depression assists the vacuum previously reduced by the piston and enables the b0 y of air entering the cylinder at considerable velocity tocontinue its movement through the interior of establish communication with the chamberu: where a depression prevails resulting the cylinder until the exhaust ports are reached.

- At this moment the velocit reaches its maximum value an one quarter revolution of the motor say 90 is effected. End of admissiow-Oomprcssioni of pure the piston increases its angular velocity and covers the exhaust openings L. The body of air impelled at a great velocity continues its movement by reason of its inertia andaccumulates in the cylinder until the in ternal pressure becomes sufiiclent to cause it to lose its velocity. At this moment the valve closes.

of the air.

' to the inner dead centre.

The piston continuing its movement approaches the head of the cylinder. The compression of the air begins and attains its maximum value when the piston moves At this moment the motor will have rotated a further 90 in all say 180.

Ignition and expansion. Exhaust of. the consumed gases.At this moment the compression of the air is such that its temperature is suflicicnt to ignite the combustible vapours injected into the cylinder. This injection commences slightly before the piston reaches the inner dead centre and terminates shortly afterwards.

The combustible'being injected gradually under pressure and vaporized on its entry into the chamber the ignition is very rapid the combustion begins, and considerably raises the temperature of the air compressed .in the cylinder consequently its pressure increases rapidly to a degree which is limited and is kept uniform during. a fraction of the stroke of the piston.

This method of injectingthe combustible makes it possible to avoid a violent and breaking strain on the piston and the cylinder thus reducing the stress on the devices:

connecting links, cams, and bearings. The mean pressure is as high as in an explosion motor but the expansion is gentler impartin greater suppleness to the motor. The question is not the forming of a more or less perfect gaseous mixture in order to r eflect its rapid ignition and a satisfactory expansion but simply the regulating of the quantity of combustible injected in order to ensure a more or less powerful expansion with the pressure retaining an almost uniform'value.

The maximum quantity of combustible to be injected is limited by the quantity of oxygen' containe in the cylinder.

At the be inning of the expansion the piston is made stationary in consequence of. the resistance ofi'ered by the cams K to'the rollers of bearings R The cylinder receives tangentially the stress resulting from the expansion of the gases. This stress may be considered as appliedto a lever whose length is equal to the radius joining the centre of the motor and the centre of the interior section cylinder. I After a certain movement of the. cylinder .during the impulsive expansion the piston begins to move and acquires an acceleration of rotation which is less than that of the cylinder until the latter has moved 90 starting from the inner dead centre.

A little in advance of the outer dead centre, the piston .frees the exhaust openings L, the section of passage of which is very great. i

The consumed gases being still at a relaof the 7 tively high pressure above that of the atmosphere pass through the openings L and expand in the open air flowing through the exhaust chamber in; in a direction opposite to the direction of rotation of the motor in order to facilitate the discharge and to section of the passage, is high. A very.

rapid decrease of pressureand of temperature is produced wh1ch causes cons derable (l8pI'SS1OIl.1I1 the cylinder.

Inorder to avoid the return of consumed.

gases to the cylinder, the admission valve opens rapidly presenting a large section of passage enabling the cold air driven by the centrifugal force against the inside of the casing to fill up the relative vacuum produced in the cylinder. This body of air follows the burned gases and passes through to the exhaust chamber w. The object of the chamber to is'to prolong the depression in the cylinder caused by the rapid expansion of the gases.

The result is a forcible current of cold air in the interior of the cylinder cooling the .sides and expelling the burned gases.

The velocity of this current of air may be made very great by precisely regulating the point at which the admission valve is opened. It will be seen that the period during which the gases burned at a high temperature are in contact with the sides of the cylinder and of the piston is reduced by this powerful scavenging action to the minimum; the quantity of heat taken up by the sides is much less and consequently the mean temperature is reduced of a revolution.

Ulearz'ng out of the combustion chamber and exhaust of hot aim-The motor acts like a fan of considerable capacity and during the period when the ports L are opened the air taken from the casing is replaced by an equal quantity coming from the atmosphere. The motor continuing to rotate the piston commences its ascending stroke and covers the exhaust openings. I

In consequence of its inertia the body of air projected at great velocity continues to penetrate into the cylinder the valve remains completely open the pressure increases slightly in the cylinder until the velocity of the produced current is nullified the air then expands and bein forced by the piston returns to the casing passing aroundthe valve that is always completely open.

A certain quantity of heat taken up in coming in contact with the sides is carried of]? by this body of air expelled from the cylinder by the piston thus the exhaust period here is a cooling period.

When the piston is at the inner dead centre the cylinder" has completed the last quarter of a revolution. It is at the starting int having completed the cycle in a sing e revolution. The same is the case with the cylinder C.

When one of the cylinders exhausts the hot air in the casing the opposite cylinder compresses a charge of air.

The consumed gas discharged through the exhaust ports L behind the pistons is drawn along by the depression in the chamber w and is also driven by the pressure of air tending to enter the cylinder from the interior of the casing. This body of hot' air is-replaced in the casing by a quantity of cold air coming from the interior. There is always a current of air in the interior of the casing which acts as a centrifugal fan.

When the pistons the b y of air in motion continues to accumulate in the cylinder in consequence of its inertia. a a Starting.-.In order that the compressions may be very forcible at starting the starting is efiected automatically by an admis sion of compressed air into the cylinders which are at the expansion stage and the pistons of which have passed the inner dead centre in the direction of rotation.

Uooling. Special 7 arrangements. Giraulation of aim-Each group of two elements, having four cylinders in all is enclosedvby a casing V in the form of a drum made of sheet aluminium having vertical partition 0 between the two elements. These drums are firmly connected with the outer cylindrical casing E also made of alumini The -whole is kept fixed and perfectly concentric to the motor. A

In the caseof an aviation motor the interior of the casing E is in communicationmeans of pipes b with an exhaust chamber.

W which opefis'into the atmosphere by way of the circular casing E.

This exhaust chamber W would be arranged on an aviation motor in the space existing between the casing E and the hood of the a paratus. It should be closed in front an in communication with'the open air through wide openings formed in-the direction opposite to that 'of travelling so as to obtain a slight depressin in theinterior.

Girculation.-Let us put the motor in motion. The body of air in contact with the sides in movement is thrown by the centrifu-' alforce against the interior sides of the rums tangentially to the exterior of the movable partof t "e The air compressed finding no outlet except the pipes b' rushes into them orts L are covered by the motor which acts as a 1 creating behind it and towards the centreof the motor a zone of depression. This relative vacuum is relieved by air coming from the interior of the casing E and passing around the drums.

he tubes in extension of the c linders are very smooth and rather small 1n diameterv thus leaving a space sufiicient for the passage of cold air, into which the cylinders furnished with longitudinal vanes plunge. These vanes are very high so as to increase the radiation surface.

After coming in contact with the sides and the vanes of the cylinder the air is projected towards the pipes creating a continuous current carrying along the burned gases as well as the air coming after each exhausis formed of a metal tube which is a good heat conductor. It transmits a certain quantity thereof to the open air.

The successive scavenging actions in the interiorof the'cylinders reduce the period during which the sides are heated and cause a very active internal circulation of air cooling the cylinders, valves and pistons and increasing the circulation of air outside.

The cooling is extremely powerful and can be regulated by varyin the section of passage at the entrance to t e circular casing E. The linear velocity of the pistons (relative velocity with relation o the cylinders) is at the maximum when t e rollers R having passed the points Mtravel along the descending portions of the cam path.

' Instead of being completely stationary at this moment, in practice the pistons are almost'stationary, but they' never move in the direction op osite to the rotation of the motor. The pro e of the cams K in moving downwards from'the point M'takes a slightly eccentric osition coming away from the point in w ich the centre of the shaft X lies at the moment when the rollers R move to M. I

. This linear velocity of the pistons with res ect to-the cylinders is equal to zero when cylinders and pistons move at the same rotary speed around the centre 0.

The rotary speed of the pistons reaches the maximum when the rollers IE move.

through the are N, M of the cams K.

When the rollers R reach M the inertia of i all the moving parts such as'co'nnec-ting lin ks attain the maximum value.-

This inertia which is very considerable is absorbed by the resistance of the gases the pressure of which increases rapidly to the inner dead centre, and only adds to the value oflthe motive effort which constitutes an appreciable advantage from the mechanical point of view.

Whatever may be the strokes or the positions of the cylinders the rollers R remain in constant contact with the cams K.

When the ports L are opened the fall of pressureis gradual and the various moving parts of the mechanism having an accelerated movement their inertia comes into action in a useful manner offering resistance preventing the rollers from leaving the This allows of very great lineal velocities being attained with minimum friction thus facilitating the lubrication of the cylinders.

The friction of the piston rings is limited by their elasticity. When' the pressures and the temperatures are at the highest the pistons being nearly stationary in space the centrifugal force has no action on the rings and thus does not impair their tightness. These rings which are very thin are grouped in twos and mounted so that their common plane of contact passes through the radius of the motor;

The centrifugal force acting on the rollers R as on the balls of a governor assist in the acceleration of the movement of the pistons, through the medium of the toggle links B, B at the moment when they should attain the maximum rotary speed and the losses of energy due'to the-inertia of the central 2 piece being thereby reduced.

The toggle links always work tractionally. The mechanical output of this motor can thus be very great and also the thermic output and consequently the total output.

I claim 1. A polycylindrical internal combustion rotary motor comprising pairs of curved cylinders'diametrically disposed with reference to a central stationary shaft about which the. motor rotates, pistons operating in said cylinders, Z-shaped central pieces carrying said pistons and rotatable about said shaft, pairs of diametrically opposed toggle links connecting the Z-shaped pieces with the cylinders, stationary cams mounted on the central shaft," and rollers mounted on the toggle joints of the toggle links, said rollers bearing freely on the exterior running surfaces of-the stationary cams and following the profile thereof.

2. A polycylindrical internal combustion rotary motor comprisin pairs of curved cylinders diametrically disposed with reference to a central stationary shaft about which the motor rotates, pistons operating in said cylinders, Z-shaped central pieces carrying said pistons and rotatable about said shaft, pairs of diametrically opposed toggle links connecting the Z-shaped pieces with the cylinders, stationary cams mounted on the central shaft and disposed on each side of the median plane of the cylinders, rollers mounted on the toggle joints of the toggle links, said rollers bearing freely on the exterior running surfaces of the stationary cams and following the profile thereof.

A polycylindrical internal combustion rotary motor comprisin pairs. of curved cylinders diametrically disposed with reference to a central shaft about which the motor rotates, expansion chambers connected with the cylinders and arranged at the periphery of the motor in a direction opposite to that of the rotation of the motor, pistons operating in said cylinders, Z-shaped central pieces carrying said pistons and rotatable about said shaft, pairs of diametrically opposed toggle links connecting the Z-shaped pieces with the cylinders, rollers mounted on the toggle joints of the toggle links and stationary cams mounted upon the central shaft, said rollers bearing freely on the exterior running surface of the cams and following the profile thereof.

In testimony whereof I have affixed my signature.

FRANQOIS ROCHEFORT. 

